Azo dyesttjffs containing a heavy



Patented Mar. 10, 1942 AZO DYESTUFFS CONTAINING A HEAVY METAL IN COMPLEX FORM Ernst Fellmer, Leverkusen-I. G.-Werk, Germany,

assignor to General Aniline & Film Corporation, a corporation of Delaware No Drawing. Original No. 2,111,559, dated March 22, 1938, Serial No. 753,785, November 25, 1933. Application for reissue November 26, 1940, Serial No. 367,297. In Germany November 25,

8 Claims.

The present invention relates to new azo dyestufis, containing a heavy metal in a complex form, more particularly it relates to azo dyestuffs which may be represented by the probable general formula:

l 4 i (N N Ra Cu wherein X stands for the hydroxy or carboxylic acid group, Y stands for the hydroxy, the amino or a substituted amino group and Z means the same as Y, wherein R means a radical of the benzene or naphthalene series, R1 stands for hydrogen or alkyl, R2 and R3 stand for radicals of diazotization component of the benzene series free from azo groups suitable for producing azo dyestuiis, and n stands for one of the numbers zero and one.

My new dyestuffs are obtainable by starting with a monoazo dyestufi of the general formula:

R N=N I 11 l t l.

wherein X stands for hydroxyl, alkoxy, halogen or the carboxylic acid group, Y and Z and R and R1 mean the same as stated above, coupling the same with a diazo compound of the benzene series free from azo groups suitable for preparing azo dyestufis if desired, coupling the diazo dyestuffs with a further diazo compound of the benzene series free from azo groups suitable for preparing azo dyestuffs and transforming the dyestuffs either prior or after the last coupling into the copper complex compounds of the corresponding o-hydroxyor o-carboxy-azo dyestuffs. It is self-understood that in case there are used as starting compounds such azo dyestuffs of the above-identified second formula, in which X stands for alkoxy or halogen, the conditions of working must be chosen in such a manner that the alkoxy group is split up or the halogen atom is replaced by a hydroxy group in the manufacture of the heavy metal complex compounds.

The new dyestuffs are in form of their alkali metal salts generally dark, watersoluble powders,

dyeing leather generally even shades of excellent fastness to light. The, dyestuffs can be suitable for dyeing both chromium and vegetable tanned leather. Further my new heavy metal compounds can be suitable for dyeing animal and vegetable fibres.

The invention is illustrated by the following examples, without being limited thereto:

Example 1.-2D.3 parts by weight of Z-anisidine-l-sulfonic acid are diazotized with 6.9 parts by weight of sodium nitrite and hydrochloric acid at 0 C. The diazotization mixture is then combined with a solution of 11 parts by Weight of resorcin in a soda-alkaline medium. The reaction mixture is then rendered weakly acid to acetic acid, 24.9 parts by weight of copper sulfate are added, the reaction mixture is refluxed for several hours, and after cooling, the copper complex compound is salted out, filtered and suspended in water; the aqueous suspension I is rendered alkaline, and the copper containing azo dyestufl is coupled in an alkaline medium with a diazo compound from 13.8 parts by weight of o-nitraniline. The dyestufif having in the free state, i. e., in the form of the free acid the following probable formula:

dyes leather, wool and silk a neutral light brown of good fastness properties.

By substituting the o-nitraniline by l-nitro- 1,3-phenylenediamine there is obtained a deeper more yellowish brown. In its free state, the dyestuff corresponds to the. following formula:

- on on v s on: N=N-C NO2 pound by heating for several hours at 70 C. with an aqueous copper ammonia solution prepared from 49.8 parts by Weight of crystallized copper sulfate. The dyestuff is isolated, in the usual manner; in its free state, i. e., in the form of the free acid it corresponds to the following probable formula:

on on s03H N=NO S OaHJ CH2 It dyes leather, wool and silk brownish-red shades.

Example 3.The diazo compound from 20.7 parts by weight of 6-chloroaniline-3-sulfonic acid is coupled in an acid medium with 11 parts by weight of resorcin, and when the coupling is complete, the monoazo dyestufi is salted out and filtered. It is then suspended in water and transformed into its copper complex compound by heating for several hours at 90-100 C. with 24.9 parts by weight of crystallized copper sulfate and 80 parts by weight of aqueous caustic soda lye of 30% strength. After cooling, the copper complex compound is isolated from the acidified reaction mixture, suspended in water and coupled in an alkaline medium with the diazocompound from 32.1 parts by weight of dehydrothiotoluidine-sulfonic acid. The dyestuff having in its free state, i. e., in the form of the free acid the following probable formula:

OH OH SOaH dyes leather neutral middle brown shades.

Example 4.The diazo compound from 24.8 parts by weight of -nitro-2-anisidine-4-sulfonic acid is coupled in an acid medium with 11 parts by weight of resorcin, and the monoazo dyestuff formed is refluxed for several hours in an aqueous acetic acid solution containing 24.9 parts of crystallized copper sulfate. The copper complex compound is isolated, coupled in soda-alkaline solution with the diazo compound from 12.7 parts by weight of p-chloroaniline, and the dyestufi is isolated in the usual manner. The dyestuff having in the free state, i. e., in the form of the free acid the following probable formula:

state, i. e., in the form of the free acid the following probable formula:

5 OCH:

dyes leather yellowish-brown shades.

By substituting the 2-anisidine-4-sulfonic acid used as final component by an equivalent quantity of p-nitram'line-3-sulfonic acid, there is obtained a dyestuff dyeing leather, wool and silk clear yellowish-brown shades.

Example 6.The diazo compound from 40.6 parts by Weight of 2-anisidine-4-sulfonic acid is coupled in a soda-alkaline medium with 11 parts by weight of resorcin. The diazo dyestuff obtained is then coupled with a diazo compound prepared from 13.8 parts by weight of diazotized p-nitraniline in a soda-alkaline medium, and the trisazo dyestuff is isolated. It is suspended in water and transformed into the double complex copper compound by heating at 70 C. with a copper ammonia solution prepared from 49.8

parts by weight of crystallized copper sulfate. The dyestufi is isolated by salting out. In its free state, i. e., in the form of the free acid it S OaH It dyes leather reddish-brown shades.

Example 7.--The diazo compound prepared from 20.7 parts by weight of 2-chloroaniline-4- sulfonic acid is coupled in an acid medium with 11 parts by weight of resorcin, and the isolated dyes leather, wool and silk middle brown shades.

Example 5.The copper complex compound prepared in accordance with Example 1 from 20.3 parts by weight of Z-anisidinei-sulfonic acid, 11 parts by weight of resorcin and 15.3 parts by weight of -nitrol-1,3-phenylenediamine is coup-led in an alkaline medium, favorably in the presence of caustic soda, with a diazo compound'prepared from 20.3 parts by weight of 2-anisidine-4- sulfonic acid. The dyestuff having in the free monoazo dyestuff is transformed into its copper complex compound in the manner described in Example 3. The copper complex compound is isolated, suspended in water and coupled in the 7 presence of sodium acetate with a diazo compound prepared from 13.8 parts by weight of pnitraniline and then in an alkaline medium in the presence of caustic soda with the diazo compound prepared from 32.1 parts by weight of dehydrothiotoluidine-sulfonic acid. The dyestufi isolated inthe usual manner having in the free with the diazo compound from 17.3 parts by state, i. e., in the form of the free acid the folweight of p-sulfanilic acid. The azo dyestufl is lowing probable formula: salted out with common salt, filtered and transdyes leather middle brown shades. formed into its chromium complex compound by Example 8.The monoazo dyestufi obtained by redissolving in water and heating in an autocoupling in an acid medium the diazo compound 5 clave at 105 C. for 1 /2 hours with chromium sulfrom 13.7 parts by weight of anthranilic acid and fate lye corresponding to 9 parts by weight of 10.9 parts by weight of m-aminophenol is heated CrzOa. The dyestufi having in its free state, i. e., for 1 /2 hours at 110 C. in an autoclave with a in the form of the free acid the following probchromium formate solution corresponding to 8 able formula:

grams of CrzOa. The dyestuff is isolated from dyes leather yellowish-brown shades. the acidified reaction mixture and coupled in an I claim: alkaline solution with the diazo compound pre- 1. Azo dyestuffs containing copper in complex pared from 21.8 parts by weight of p-nitranilineform 0f the general u 3-sulfonic acid. The dyestuff having in its free state, i. e., in the form of the free acid the fol- H033 l lowing probable formula: RN=N H 9 -Cu O O OH OH H OH (N=NRs)n C wherein X stands for a member of the group consisting of hydrogen, sulfonic acid, and amino groups, Y stands for a member of the group consisting of hydrogen and N02, R2 stands for a member of the group consisting of N02 and a benzthiazole radical, Ra stands for a radical of a diazotization component of the benzene series free from azo groups, and n stands for one of the numbers 0 and 1, being in the form of their alkali metal salts generally dark, watersoluble powders, dyeing leather generally even shades of excellent fastness to light.

dyes leather yellowish-red light to middle brown shades, wool and silk yellowish-brown shades.

Example 9.The diazo compound prepared from 46.8 parts by weight of 4-nitro-2-aminophenol-B-sulfonic acid is coupled with 10.8 parts by weight of m-phenylenediamine, the coupling mixture being rendered alkaline in order to complete the coupling. The disazo dyestuff is isolated f l z i i i gi i gigi j copper m complex from the acidified solution and transformed into the double chromium complex compound by suss on: N=N- 11, pending in water and refluxing for several hours with chromium sulfate solution in a quan- ON=N 011 X tity corresponding to 16 parts by weight of CrzOa. l I I J The chromium complex compound is liberated OH OB(N=NR3)1|Q from the eXceSS Ch om um Su a e SolutiOn wherein X stands for a member of the group con- Chrom um Ox d yd a e. respectively, and the sisting of hydrogen, sulfonic acid and amino reaction mixture is Worked up in the usual mangroups, R t d for a member of the group i 8 The y s fi having the e l consisting of the N02 and a'benzthiazole radical, in the for of the f e 6. the followmg P R3 stands for a radical of a diazotization comable formula: ponent of the benzene series free from azo groups, 011 and 1!. stands for one of the numbers 0 and 1, i being in the form of their alkali metal salts gen- C N=N- H, 0H s 03H erally dark, watersoluble powders, dyeing leather I I I I generally even shades of excellent fastness to N0: N=N-- or, light.

l J a 3. The azo dyestufi having in the form of its o, free acid the following formula: dyes leather, and especially glac leather, deep OH OH blackish-brown shades. N=N

Example 10.The monoazo dyestufi prepared chloro-2-aminophenol-4-sulfonic acid and 27.? 303E parts by weight of 2-(p-toluenesulfo)-amino- N by coupling 22.3 arts b wei ht of diazotized 6- s0 H N=N- o p y g a /Q S Cu C :J l-cresol is coupled in a soda alkaline medium dyeing leather neutral middle brown shades.

4. The azo dyestuff having in its free state 'the following formula:

O SOaH N=N NOT Cu IITH: dyeing leather, wool and silk yellowish brown shades of good fastness properties.

5. Complex metal compounds of disazo dyestuffs of the general formula:

in which both Rs stand for aryl radicals of the benzene and naphthalene series, of which at least one contains a lake-forming group, which complex metal compounds are brown to black colored powders soluble in water and dyeing animal fibers, particularly leather, uniform brown tints of good fastness properties.

7. Complex metal compounds of disazo dyestuffs of the general formula:

RN=N N=NR in which both R's stand for phenyl radicals, of which at least one contains a lake-forming group, which complex metal compounds are brown to black colored powders soluble in water and dyeing animal fibers, particularly leather, uniform brown tints of good fastness properties.

8. Complex metal compounds of disazo dyestuffs of the general formula:

in which both its stand for phenyl radicals, of which at least one contains a hydroxy group standing in ortho-position to the azo group, which complex metal compounds are brown to black colored powders soluble in water and dyeing animal fibers, particularly leather, uniform brown tints of good fastness properties.

ERNST FELLMER. 

